If you want to use the 3DR telemetry modules with your Android Tablet, you will need to either use a OTG cable, or buy a micro USB to regular USB adapter to fit onto the ground module of the unmanned telemetry kit.

Yeah they do come with the firmware installed and setup but its fairly easy to configure via mission planner. But if you ever have any questions or problems just ask here on dronetrest and I will try to help